barplot with multiple colums as x-axis

Question

Given a data frame like this:

IDPLACES AMERICAN.EXPRESS VISA MASTERCARD CASH
201220                  0    1          0    1
201321                  1    1          1    1
201422                  0    0          0    1
201525                  1    1          1    1

IDPLACES are restaurants.

I want to create a barplot with each type of payment on the x-axis with the height of the bars indicating the number of restaurants accepting that payment type. Any ideas?

Thank you! But, I have to create it with ggplot2, and when I run this — Lilian, Dec 20 '16 at 19:53
You likely need to reshape your dataset. See some examples of that [here](http://stackoverflow.com/questions/22305023/how-to-get-a-barplot-with-several-variables-side-by-side-grouped-by-a-factor) and [here](http://stackoverflow.com/questions/15910987/stacking-multiple-columns-on-a-geom-bar-in-ggplot2). — aosmith, Dec 20 '16 at 19:59

score 0 · Accepted Answer · answered Dec 20 '16 at 21:24

Make the data frame.

df <- data.frame(idplaces = c("201220","201321","201422","201525"),
                 Amex = c(0,1,0,1),
                 visa = c(1,1,01,1),
                 mastercard = c(0,1,0,1),
                 cash = c(1,1,1,1))

First, you have to reformat the data (that's often the case for ggplot2). The way to reformat it depends on how you intend to plot it. I'll be using geom_bar(), which defaults to having the height of the bars represent the number of cases in the data frame. So I'll reformat to a long data frame using gather from the tidyr package, and then filter out any cases where the restaurant doesn't accept that method. The resulting dataframe will have columns for the restuarant id, and one row for each of the payment methods each restaurant accepts.

> df_long <- df %>% 
 +  gather("method", "accepts", -idplaces, factor_key = TRUE) %>% 
 +  filter(accepts == 1)

> df_long
   idplaces     method accepts
1    201321       Amex       1
2    201525       Amex       1
3    201220       visa       1
4    201321       visa       1
5    201422       visa       1
6    201525       visa       1
7    201321 mastercard       1
8    201525 mastercard       1
9    201220       cash       1
10   201321       cash       1
11   201422       cash       1
12   201525       cash       1

To plot with methods on the x-axis, set x=method in aes().

> ggplot(df_long, aes(x=method)) + 
  + geom_bar()

@Lilian ; if Rose's solution has answered your question, you can click the tick to mark it. — user20650, Dec 21 '16 at 15:30

barplot with multiple colums as x-axis

1 Answers1